Rotary well-drilling bit



' G. GARTLING ROTARY vWELL DRILLING BITA Filed March .28; 1922 ITW-4 f Patented July5, 1927. t

UNITED STATES GEORGE GA'n'rEING, oE Los ANGELES, cALIFoRNTA.

I ROTARY `Wllilll'lIJDR-ILLIN'G BIT.

.Application led March 28, 1922. Serial No. 547,410.

An object of this invention/ is to provide a rotary well drilling bit, the cutters of which can be economically, made of high l grade steel and can be re'sharpened withu ease.

The invention is broadly new, basic and pioneer in that I. provide a. c'utterbody adapted to rotate on a cential axis and having gains' on its front sides and clamping 1o plates therefor that are adapted to clamp the shanks yof detachable cutters. Said front sides and clamping plates are recessed to hold ,the shanks non-ratatably in clamping 4 slots. Objects of the invention are simplicity, strength of construction, ease of assembling and disassembling and security against loss of the cutters.

An object is to so construct the stock as 2o to aord maximum strength and to afford maximum convenience of assembly and disassembly.

Another object is to so construct and arrange4 the cutters as to secure the most rapid cutting. YAn advantage gained with this invention arises from application of the cutters at an acute angleto the surface to be cut so as to cut most eiiciently.

Other objects, advantages and features of invention may appear'from the accompany,-

ing drawing, the sub'joined detail description and the appended claims.

The accompanying -drawing illustrates the invention.

Figure 1 is an elevation of a rotary drill bit constructed in accordance with this invention. l

Fig. 2 is a bottom view of the bit shown in Fig. l. Y

Fig.- 3 is a bottom view of the stock and Vclamping plates (Figs. 1 and 2) secured to gether by bolts and omitting the cutters.

Fig. 4 is a section on line wt, Fig. 2.

Fig. 5 is a section on line m5, Fig. 4.

Fig. 6 is an edge view of the bit shown in Flg. 1.

Fig. 7 is a section on line m7, Fig. l.

Fig. 8 is a top view of oneof the cutters.

Fig. 9 is a side view of one of the cutters.

The bit is provided at its upper end with a taper screw' 1, and a stock abutting cylindrical collar 2 beneath which is the body 3 extendin endwise fromy and laterally beyond sai collar. The bit may be constructed 55 to turn from right to left or may be reversely constructed, as desired. A bit adapted to turn from right to left is shown 1n the drawings. Each face of the bit body 3 comprises a front side or an advancing face a and a back side or retreating face b reversely arranged on the opposite sides ol the medial plane e of the bit, such plane c extends transversely through the bit at right angles to the advancing face a or retreating face b.

The advancing face a on each side of the medialc plane 0 is provided with a gain l cut about half-way through the body 3, and the floor of said gain is provided wi.-- desired number ofeccentric semi-hexagonal shank-receiving grooves or seats 5 that are parallel with the medial plane c; and into cach gain there is fitted a clamping plate or piece 6 provided with like grooves 5', co-operating with the grooves 5. The eccentric cutters are chisels 7 having shanks 8 adaptedto fit the grooves 5 and 5 and are of such diameter as to space the floor of the gain and the inside wall of the clamping plate apart as at 9 sufiiciently to allow the Shanks to be firmly and non-rotatably clamped between the elampingplate and the floor of the gain when the bolts l0 are tightened. Said bolts are shown 'as provided with nuts 1l and washers 12. The Shanks 8 are shown as hexagonal in form and the grooves 5 and 5 are semi-hexagonal in form so that the clamped cutters Will be non-rotatable and may be easily removed and replaced when the clamp pieces 6 are removed or suiiiciently loosened for the purpose. The bolts 10 are applied in such number and arrangement as to enable the workman to tightly clamp the parts together and to positively fix the cutters.

The bolts may be provided with any locknut or other suitable means not shown for preventing the nuts from unscrewing.

The tips or chisels 7 of the cutters are preferably bent forward in the direction of rotation as indicated in Figs. 2, 5, 6, 8 and 9, and may be staggered as to a horizontal plane as indicated in Figs. 1, and 4. That is each successive inwardly spaced cutter is arranged with its `tip above the tip of the adjacent cutter.

In practice the cutters and clamping plates are applied and Withdrawn as desired and when the cutters become worn they will be removed, upset and sharpened. This is done Htl from time to time until the shank is too short for practical use, when a new cutter may be supplied.n

In the fish-tail form of bit shown in Figs. 1 and 4 the staggered arrangement of cutters enables the tool to cut more rapidly as is well known to the art. It is understood, however, other arrangements of cutters may be made vwithout departing from the spirit of this invention.

The usual water courses 13 through the taper screw and collar open into the medial groove 14 so as to direct water supplie\d from a source not shown to the center of the cut. f

The body of the bit below the taper thread and collar Stock comprises two shoulders 15, a central stem 16, and two backings 17 and 17 integral with said shoulders and stem and in offset or staggered relation to each other so that the pressure to drive the cutters is well supported andthe tool is compact.

and strong.

The floors of the gains which are the front faces of the backings 17 and 17 are practically in the same vertical plane and are radial to the axis of rotation and? the de th of shank seats 5 and 5- are somewhat ess than' half the diameter of the slianks so as to insure a tight frictional grip on the Shanks;

1. A rotary well drilling bit comprising a body having gains on its forward faces; clamping pieces in said gains; cutters having Shanks between the clamping pieces and floor of the gains; and means to secure the cutter shanks between the clamping pieces and the Hoor of the gains;

2. A rotary well drilling bit having faces and comprising a bodyo having gains on opposite sides of amedial plane extending transversely through the bit at right angles to said faces; clamping pieces in said gains; cutters having Shanks; and means adapted to non-rotatably hold said shanks between said clamping pieces and gains, said gains being practically in the same vertical plane and radial to the axis of rotation.

3. A rotary well drilling bit comprising a body having gains on its forward faces; clamping pieces in said gains; cutters having Shanks between the clamping pieces and Hoor of the gains; and means to secure the cutter shanks between the clamping pieces and the floor of the gains, said cutters having cutting tips bent forward and extending aslant v non-rotatably clamp said cutter shanks in said grooves.

5. A rotary well drilling bit comprising a body having gains the floors of which are provided with semi-hexagonal grooves; clamping plates tted in said gains and provided with semi-hexagonal grooves adapted to cooperate with the grooves in said gains; cutters having hexagonal Shanks; and means adapted to clamp said cutter Shanks in said grooves. Y

6. The integral'rotary drill bit stock 'for detachable cutters and therefor substantially as set forth said stock comprising a taper thread and a collar, shoulders, stem and backings; said backings being in offset relation to each other to accommodate said clamping means so as to apply power at the rear of cutter Shanks fixed on opposite sides of the stem, when the stem is rotated in the appropriate direction substantially as set forth. I

' 7. A rotary Well drilling bit comprising a body having gains on its forward faces;

clamping pieces in said gains; cutters having shanks between the clamping pieces and floor of the gains; and means to secure the cutter slianks between the clamping pieces and the floor of the gains, said cutters having cutting tips bent forward and extending aslant forwardly and downwardly .from the cutter Shanks; said cutter being arranged with the tips of each successive inwardly spaced cntter above the tip of the adjacent cutters.

In testimony whereof, I have hereunto set my hand at Los Angeles, California, this 20th day of March, 1922.

GEORGE GARTLING.

clamping means 

